AMD Details The Benefits DirectX 12 Has For Gamers On Multi-GPU Setups

In a few months the world will get the first taste of what DirectX 12 offers gamers and developers. AMD recently released some slides to show what kind of technolgies will be available for their lineup of graphics cards, and the performance benefits that can be realised.

So, we should all know by now that DirectX 12 is a low level API that will allow close-to-the-metal access to hardware allowing for a fine-grain control to push the capabilities of GPUs forward. It’s no secret that the release of newer GPUs has slowed down immeasurably, with even the current crop of “new” GPUs from AMD being rebrands. Performance, it seems, needs to be found on another playing field, and DirectX 12 is offering just that, with the buzzword mainly being “Multiadapter”, with AMD offering “Explicit Multiadapter” and “Multi-GPU performance”

A few weeks ago Microsoft published some of their findings on cross-IHV performance using DX 12, and how an Intel iGPU could assist in offering some rendering power to the discrete Nvidia GPU. This time AMD are showing what DX12 can do on the Red side, by allowing for a higher FPS, new multi-gpu configurations and unique frame rendering methods.

Higher FPS is going to be achieved by leveraging proper native support for Multi-GPU configurations in DX12, which essentially means that the developers will be able to access the resources of your AMD GPU directly and fine tune or distribute work across GPUs.

AMD will leverage DX 12 to make use of dual graphics across their APU and GPU line-up, much like how Microsoft showed an Intel iGPU and a discrete Nvidia GPU. However, AMD’s on-board dedicated Radeon GPU core is a lot more powerful than an Intel iGPU, and DX 12 will allow developers to offload graphics work to an AMD APU.

AMD also explore how DX 12 can change the rendering of frames. Under DX 12 a multi-GPU can output frames in SFR(split-frame rendering) as opposed to the stuttering prone alternate frame rendering mechanism in DirectX 11. Instead of each GPU rendering one frame each, each GPU will now render half of the same frame, thus reducing overhead, increasing responsiveness and reducing the amount of stutter involved in multi-GPU setups.

Mentioned a while ago in a tweet, the use of DX 12 will allow something unprecedented in multi-GPU setups–the combination of memory pools. Under previous DirectX versions the easiest way to keep both graphics cards working together properly was to limit their workloads to their own memory pools, so none of the workload was divided. In DirectX 12, the memory pool is not open to all and shared across all GPUs, so that if a frame is particularly memory heavy, the GPU rendering it can access the RAM on the other cards in the configuration. This could not come at a better time since the use of memory on GPUs has started to reach ridiculous levels, with the likes of 4K displays and graphics cards like the Titan X reaching 12GB and the R9 290X shipping with 8GB.

To bring it back down to earth and offer gamers some assurances that this is not merely a pipe dream for AMD cards, they have included two games, Dues Ex:Mankind Divided and Ashes of the Singularity, which are specifically being developed with DX12 in mind. These are two games optimised for AMD cards under the Gaming Evolved program with technology like TressFX 3.0 coming to Dues Ex. I half expected to see a “pre-order now” tag, but thankfully AMD still have some dignity left not to push pre-orders right away.

I for one think DirectX 12 is going to be something PC gaming is going to relish for the next few years, especially when we consider the amount of high display peripherals that are going to require a massive amount of memory bandwidth and nuance of coding to perform: the likes of VR technology, 8K displays, the my own dream of CDPR using DX 12 to released an Enhanced Edition of the Witcher 3 on PC which looks like its 2013 in-game footage. With the likes of The Witcher 3 and Batman Arkham Knight being a massive selling feature for Nvidia cards, having some DX 12 Gaming Evolved titles in the pipeline are a good show of commitment from AMD, especially considering how lackluster their Gaming Evolved program has been of late.